CVE-2019-11728

critical

Published — · Modified —

CVSS v3

—

CVSS v2

—

VIR risk

9.5

Description

The HTTP Alternative Services header, Alt-Svc, can be used by a malicious site to scan all TCP ports of any host that the accessible to a user when web content is loaded. This vulnerability affects Firefox < 68.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2019-11728

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-201907-4

OS impact

OS	Version	Status	Fixed in
arch		fixed	`68.0-1`
debian	sid	fixed	`68.0-1`

References

https://security.archlinux.org/ASA-201907-4
https://security-tracker.debian.org/tracker/CVE-2019-11728

Verify integrity in audit chain (admin only). AS-IS.